Modern electronic devices such as cameras, smartphones, tablet computers, etc., are typically equipped with image sensors (e.g., camera modules). The image sensors are used to capture photographs of various scenes for storage and/or display in the electronic devices. After a photograph has been captured and stored, image processing functions in such electronic devices may allow a user to enhance or improve the photograph according to his or her preference. For example, some electronic devices may allow a user to view a photograph and select a desired editing function among a variety of functions such as auto-enhance, crop, rotate, red eye reduction, etc.
Conventional electronic devices equipped with an image sensor are typically used to capture photographs of a variety of types of scenes and objects. For example, such electronic devices may be used to photograph a scene that includes text objects such as a document or a sign with text and non-text objects such as flowers, walls, doors, light sources, etc. However, since the scene includes the non-text objects, the image sensor of such electronic devices may not be able to capture a photograph that is optimized for the text objects in the scene.
In addition, conventional electronic devices may be configured to focus at a predetermined portion of a scene such as a center portion of the scene rather than a portion that includes a desired text object. Accordingly, the text object in a photograph of the captured scene may not be of sufficient image quality. Some electronic devices may also allow a user to manually specify a desired portion of the scene to be focused on a display screen. However, manually selecting the desired portion of the scene while holding an electronic device may not be very convenient to the user.